The Study For Glass Inclusions From Quartz Enclave In Alkaline-rich Porphyry In Western Yunnan,China

The alkaline-rich intrusive rocks formed in the Jinshajiang-Ailaoshan ancient suture zone and its two sides in western yunnan.The related mantle fluid is an important part of the deep geological process,and the multi-metal deposit is the external manifestation of its deep geological process.Previous studies have aimed at alkaline-rich intrusive rocks in western yunnan about petrography,geochemistry and chronology,but for the origin of magma,the relationship between the magma and the fluid as well as to realize the interaction and evolution is still controversial.Based on the existing research results,this paper focuses on the study of lithology and temperature measurement and fluid geochemistry of glass and fluid inclusions in quartz inclusions.The main achievements are as follows:?1?The temperature measurement results of the various inclusions in quartz enclave are range of 950?¹050?,and the temperature measurement results of symbiosis pure CO₂ inclusions are range of 28.9?²9.5?.The presence of the glass inclusions in the quartz enclave represents a high temperature environment,but the symbiosis pure CO₂ inclusions are a low density inclusions?0.318⁰.336 g/cm³?.So that the glass inclusions which with a higher uniform temperature obtained a relatively low pressure in the CO₂ diagram,substantially the presence of low density pure CO₂ inclusions represents low pressure environment of molten fluid.The calculated pressure of the fluid inclusions in the same period is much greater than the pressure calculated by the glass inclusions.and under different pressure conditions,the degree of miscibility between the melt and the fluid is different,which indicating that the pressure is the dominant factor that causes magma-fluid immiscibility.?2?The metasomatism of the mantle fluid in the depth triggers the formation of the metasomatic enriched mantle.In the background of tension,strike-slip,shear tectonic structure,the silicon-unsaturated alkali-rich magma originated from the metasomatic enriched mantle source area contains silicon-rich and alkali-rich mantle fluid which includes the ore in immiscible way.And the inhomogenous ultramafic-mafic molten lava captured by the silicon-unsaturated alkali-rich magma increases along the deep fault zone with the simultaneous migration rise,with its invasion causing the deep crustal rocks to partially melt to form silicon supersaturated felsic magma.?3?The magmatism of after partial melting of crust caused by deep processes can be divided into two parts:First,silicon unsaturated rich alkaline magma which from the metasomatic enriched mantle,at the same time trigger invasion,and then in the immiscible way capture a small amount silicon supersaturated felsic magma which experience remelting,and then simultaneously migrate to the upper crustal crystallize form rocks,and eventually formed silicon unsaturated alkali-rich porphyry containing granite inclusions and ultramafic-mafic magmatic inclusions and a few special inclusions?such as quartz inclusions?.Second,the silicon supersaturated felsic magma formed by deep crustal rocks partially melted,in immiscible way to capture the silicon-rich and alkali-rich mantle fluid which include the ore,which separated by invasion magma,and then in the process of simultaneously migrate to the upper crust,the fluid is accompanied by magmatic crystallization and diagenetic alteration,finally the formation of silicon-rich and alkali-rich granite which include the ore and the corresponding polymetallic deposits.